A Pediatric AIDS Clinical Trials Group at NYU Medical Center will be expanded to provide a facility which will perform the following: 1) devise innovative protocols to be implemented locally and in multicenter settings; 2) integrate our ability to enroll pregnant women at high risk for HIV infection into studies which describe the natural history of HIV infection in their newborns (thereby identifying HIV children at an early age) with the capacity to enroll these HIV infected children into therapeutic Phase I/II/III trials which will evaluate promising antiviral and immunomodulatory drugs; 3) enroll other HIV infected children either diagnosed by our group or referred by others into Phase I/II/III trials; 4) interact with the adult component of the ATEU as a referral source for immunologically characterized HIV infected parents of our patients; 5) act as a pediatric referral source for other investigators studying heterosexually active adults who are HIV infected; 6) perform routine and state of the art laboratory procedures in an efficient manner to optimize the small volume blood and body fluid specimens available from newborns and smaller children; and 7) provide the capability to perform pharmacokinetic studies on new drugs using small volumes of blood and body fluids. This effort will be facilitated by the availability of a social worker dedicated to the needs of HIV infected families and interactive with the Bureau of Special Services for Children in New York in order to overcome social obstacles.